Paracetamol (Acetaminophen) in stroke 2 (PAIS 2): protocol for a randomized, placebo-controlled, double-blind clinical trial to assess the effect of high-dose paracetamol on functional outcome in patients with acute stroke and a body temperature of 36.5 °C or above

Immunodepression, Infections, and Functional Outcome in Ischemic Stroke

Stroke remains one of the main causes of mortality and morbidity worldwide. Immediately after stroke, a neuroinflammatory process starts in the brain, triggering a systemic immunodepression mainly through excessive activation of the autonomous nervous system. Manifestations of immunodepression include lymphopenia but also dysfunctional innate and adaptive immune cells. The resulting impaired antibacterial defenses render patients with stroke susceptible to infections. In addition, other risk factors like stroke severity, dysphagia, impaired consciousness, mechanical ventilation, catheterization, and older age predispose stroke patients for infections. Most common infections are pneumonia and urinary tract infection, both occur in ≈10% of the patients. Especially pneumonia increases unfavorable outcome and mortality in patients with stroke; systemic effects like hypotension, fever, delay in rehabilitation are thought to play a crucial role. Experimental and clinical data suggest that systemic infections enhance autoreactive immune responses against brain antigens and thus negatively affect outcome but convincing evidence is lacking. Prevention of poststroke infections by preventive antibiotic therapy did not improve functional outcome after stroke. Immunomodulatory approaches counteracting immunodepression to prevent stroke-associated pneumonia need to account for neuroinflammation in the ischemic brain and avoid further tissue damage. Experimental studies discovered interesting targets, but these have not yet been investigated in patients with stroke. A better understanding of the pathobiology may help to develop optimized approaches of preventive antibiotic therapy or immunomodulation to effectively prevent stroke-associated pneumonia while improving long-term outcome after stroke. In this review, we aim to characterize epidemiology, risk factors, cause, diagnosis, clinical presentation, and potential treatment of poststroke immunosuppression and associated infections.

Effects of a 4-Step Standard Operating Procedure for the Treatment of Fever in Patients With Acute Stroke

Background and Purpose: Fever in the acute phase of stroke leads to an unfavorable clinical outcome and increased mortality. However, no specific form of effective fever treatment has been established, so far. We analyzed the effectiveness of our in-house standard operating procedure (SOP) of fever treatment. Methods: This SOP was analyzed for a period of 33 weeks. Patients with cerebral ischemia (ischemic stroke, transient ischemic attack) or cerebral hemorrhage (intracerebral, subarachnoid) and body temperature elevation of ≥ 37.5°C within the first 6 days after admission were eligible for inclusion in the analysis. The results of SOP group, who's data have been collected prospectively were then compared with a historical control group that had been treated conventionally 1 year earlier in the same period. The data of control group have been collected in retrospect. The primary endpoint was the total duration of the fever for the first 6 days after admission to the stroke unit. Results: A total of 130 patients (mean age of 78 ± 12) received 370 antipyretic interventions. Sequential application of paracetamol (n = 245), metamizole (n = 53) and calf compress (n = 15) led to significant reduction in body temperature. In patients who did not respond to these applications, normothermia could be achieved after infusion of the cooled saline solution. Normothermia could be achieved within 120 min in more than 90% of the cases treated by the SOP. The SOP reduced the fever duration in the 6 days significantly, from 12.2 ± 2.7 h [95% confidence interval (CI) for mean] in the control group to 3.9 ± 1.0 h (95% CI) in the SOP group (p < 0.001). The SOP was rated to be reasonable and effective. Conclusion: Our in-house SOP is cost-efficient and effective for fever treatment in stroke patients, that can be implemented by local health care professionals.

Critical care management of the patient with an acute ischaemic stroke

Acute ischaemic stroke is a leading cause of morbidity and mortality worldwide. In the UK alone, there are more than 100 000 strokes per year, causing 38 000 deaths. While the incidence remains high, there has been significant medical progress in reducing mortality following a stroke. Admission of patients to specialised stroke units has led to an improvement in clinical outcomes, but the role of intensive care is less well defined. This article reviews the current critical care management and neuro-therapeutic options after an acute ischaemic stroke.

Role of the nurse in the hyperacute care and management of patients following stroke

Stroke is a medical emergency that affects millions of people worldwide each year. The first 24-72 hours following a stroke is a critical stage in the patient's management because deterioration can occur during this period. Hyperacute care is a time-sensitive method of managing stroke that has improved the provision of holistic and evidence-based stroke care. This article describes the care and management that patients require in the first 24-72 hours following stroke. It details the evidence-based practice that this involves, and explains the role of the nurse in providing hyperacute care.

Targeted Temperature Management in Brain Injured Patients

Evidence from animal models indicates that lowering temperature by a few degrees can produce substantial neuroprotection. In humans, hypothermia has been found to be neuroprotective with a significant impact on mortality and long-term functional outcome only in cardiac arrest and neonatal hypoxic-ischemic encephalopathy. Clinical trials have explored the potential role of maintaining normothermia and treating fever in critically ill brain injured patients. This review concentrates on basic concepts to understand the physiologic interactions of thermoregulation, effects of thermal modulation in critically ill patients, proposed mechanisms of action of temperature modulation, and practical aspects of targeted temperature management.

Targeted Temperature Management in Brain Injured Patients

Evidence from animal models indicates that lowering temperature by a few degrees can produce substantial neuroprotection. In humans, hypothermia has been found to be neuroprotective with a significant impact on mortality and long-term functional outcome only in cardiac arrest and neonatal hypoxic-ischemic encephalopathy. Clinical trials have explored the potential role of maintaining normothermia and treating fever in critically ill brain injured patients. This review concentrates on basic concepts to understand the physiologic interactions of thermoregulation, effects of thermal modulation in critically ill patients, proposed mechanisms of action of temperature modulation, and practical aspects of targeted temperature management.

Challenges in the Anesthetic and Intensive Care Management of Acute Ischemic Stroke

Acute ischemic stroke (AIS) is a devastating condition with high morbidity and mortality. In the past 2 decades, the treatment of AIS has been revolutionized by the introduction of several interventions supported by class I evidence-care on a stroke unit, intravenous tissue plasminogen activator within 4.5 hours of stroke onset, aspirin commenced within 48 hours of stroke onset, and decompressive craniectomy for supratentorial malignant hemispheric cerebral infarction. There is new class I evidence also demonstrating benefits of endovascular therapy on functional outcomes in those with anterior circulation stroke. In addition, the importance of the careful management of key systemic physiological variables, including oxygenation, blood pressure, temperature, and serum glucose, has been appreciated. In line with this, the role of anesthesiologists and intensivists in managing AIS has increased. This review highlights the main challenges in the endovascular and intensive care management of AIS that, in part, result from the paucity of research focused on these areas. It also provides guidelines for the management of AIS based upon current evidence, and identifies areas for further research.

Effect of paracetamol (acetaminophen) on body temperature in acute stroke: A meta-analysis

PURPOSE

The objective of this study was to assess the efficacy of paracetamol (acetaminophen) on body temperature in acute stroke.

METHODS

Medline, Cochrane Central Register of Controlled Trials, EMBASE, Chinese BioMedical Literature Database, China National Knowledge Infrastructure, and the World Health Organization (WHO) International Clinical Trials Registry Platform were searched electronically. Relevant journals and references of studies included were hand-searched for randomized controlled trials (RCT) and controlled clinical trials (CCT) regarding the efficacy of paracetamol (acetaminophen) on body temperature in acute stroke. Two reviewers independently performed data extraction and quality assessment. Data were analyzed using RevMan 5.3 software by the Cochrane Collaboration.

RESULTS

Five studies were included. To compare the efficacy of paracetamol (acetaminophen) in acute stroke, the pooled RR (Risk Ratio) and its 95% CI of body temperature reduction at 24h from the start of treatment were -0.3 (95% CI: -0.52 to -0.08), with statistical significance (P=0.007). Consistently, the pooled RR (Risk Ratio) and its 95% CI of body temperature at 24h from the start of treatment were -0.22 (-0.29, -0.15), with statistical significance (P<0.00001). When analyzing the body temperature reduction after 5days from the start of treatment, the pooled RR (Risk Ratio) and its 95% CI were 0.04 (95% CI: -0.20 to 0.29), with no statistical significance (P=0.73). For functional outcome (mRS≤2) analysis, the pooled RR and its 95% CI were 1.08 (0.88, 1.32), with no statistical significance (P=0.45). In addition, the difference of serious adverse events between acetaminophen and placebo was 0.86 (95% CI: 0.62 to 1.2), with no statistical significance (P=0.27).

CONCLUSION

Acetaminophen was revealed to have some favorable influence in body temperature reduction in acute stroke, but showed no important effect on improving functional outcome and reducing adverse events of patients.

WHAT THIS PAPER ADDS

What is already known on this subject? Paracetamol (acetaminophen) is one of the most commonly used antipyretic drugs and has some capability to reduce body temperature through acting on central nervous system.

WHAT THIS STUDY ADDS

Acetaminophen showed some capability to decrease body temperature for acute stroke. Acetaminophen could not improve functional outcome and reduce adverse events of patients with acute stroke.

PAIS 2 (Paracetamol [Acetaminophen] in Stroke 2): Results of a Randomized, Double-Blind Placebo-Controlled Clinical Trial

BACKGROUND AND PURPOSE

Subfebrile body temperature and fever in the first days after stroke are strongly associated with unfavorable outcome. A subgroup analysis of a previous trial suggested that early treatment with paracetamol may improve functional outcome in patients with acute stroke and a body temperature of ≥36.5°C. In the present trial, we aimed to confirm this finding.

METHODS

PAIS 2 (Paracetamol [Acetaminophen] in Stroke 2) was a multicenter, randomized, double-blind, placebo-controlled clinical trial. We aimed to include 1500 patients with acute ischemic stroke or intracerebral hemorrhage within 12 hours of symptom onset. Patients were treated with paracetamol in a daily dose of 6 g or matching placebo for 3 consecutive days. The primary outcome was functional outcome at 3 months, assessed with the modified Rankin Scale and analyzed with multivariable ordinal logistic regression. Because of slow recruitment and lack of funding, the study was stopped prematurely.

RESULTS

Between December 2011 and October 2015, we included 256 patients, of whom 136 (53%) were allocated to paracetamol. In this small sample, paracetamol had no effect on functional outcome (adjusted common odds ratio, 1.15; 95% confidence interval, 0.74-1.79). There was no difference in the number of serious adverse events (paracetamol n=35 [26%] versus placebo n=28 [24%]).

CONCLUSIONS

Treatment with high-dose paracetamol seemed to be safe. The effect of high-dose paracetamol on functional outcome remains uncertain. Therefore, a large trial of early treatment with high-dose paracetamol is still needed.

CLINICAL TRIAL REGISTRATION

URL: http://www.trialregister.nl. Unique identifier: NTR2365.

Normothermia and Stroke

OPINION STATEMENT

In the past two decades, there has been much focus on the adverse effect of fever on neurologic outcome, the benefits of hypothermia on functional outcomes, and the interplay of associated complications. Despite decades of experience regarding randomized, safety and feasibility, case-controlled, retrospective studies, there has yet to be a large, randomized, multicenter, clinical trial with the appropriate power to address the potential benefits of targeted temperature modulation compared to hypothermia alone. What remains unanswered is the appropriate timing of initiation, duration, rewarming speed, and depth of targeted temperature management. We learn from the cardiac arrest literature that there is a neuroprotective value to hypothermia and, most recently, near normothermia (36 °C) as well. We have also established that increased depths of cooling are associated with increases in shivering, which warrant more aggressive pharmacologic management. Normothermia also has the advantage of allowing for more rapid clearance of sedating medications and less confounding of neuroprognostication. More difficult to quantify is the increased nursing and patient care complexity associated with moderate hypothermia compared to normothermia. It remains crucial, for those patients who are being considered for hypothermia/normothermia, to be cared for in an experienced ICU, driven under protocol, with aggressive shivering management and an expectation and acceptance of the complications associated with targeted temperature management. If targeted temperature management is not of consideration, then aggressive fever control should be undertaken pharmacologically and non-invasively, as they have been shown to be safe.

Critical care in acute ischemic stroke

Most ischemic strokes are managed on the ward or on designated stroke units. A significant proportion of patients with ischemic stroke require more specialized care. Several studies have shown improved outcomes for patients with acute ischemic stroke when neurocritical care services are available. Features of acute ischemic stroke patients requiring intensive care unit-level care include airway or respiratory compromise; large cerebral or cerebellar hemisphere infarction with swelling; infarction with symptomatic hemorrhagic transformation; infarction complicated by seizures; and a large proportion of patients require close management of blood pressure after thrombolytics. In this chapter, we discuss aspects of acute ischemic stroke care that are of particular relevance to a neurointensivist, covering neuropathology, neurodiagnostics and imaging, blood pressure management, glycemic control, temperature management, and the selection and timing of antithrombotics. We also focus on the care of patients who have received intravenous thrombolysis or mechanical thrombectomy. Complex clinical decision making in decompressive hemicraniectomy for hemispheric infarction and urgent management of basilar artery thrombosis are specifically addressed.

Medical management of intracerebral haemorrhage

The global burden of intracerebral haemorrhage (ICH) is enormous. Developing evidence-based management strategies for ICH has been hampered by its diverse aetiology, high case fatality and variable cooperative organisation of medical and surgical care. Progress is being made through the conduct of collaborative multicentre studies with the large sample sizes necessary to evaluate therapies with realistically modest treatment effects. This narrative review describes the major consequences of ICH and provides evidence-based recommendations to support decision-making in medical management.

Should we treat pyrexia? And how do we do it?

The concept of pyrexia as a protective physiological response to aid in host defence has been challenged with the awareness of the severe metabolic stress induced by pyrexia. The host response to pyrexia varies, however, according to the disease profile and severity and, as such, the management of pyrexia should differ; for example, temperature control is safe and effective in septic shock but remains controversial in sepsis. From the reported findings discussed in this review, treating pyrexia appears to be beneficial in septic shock, out of hospital cardiac arrest and acute brain injury.Multiple therapeutic options are available for managing pyrexia, with precise targeted temperature management now possible. Notably, the use of pharmacotherapy versus surface cooling has not been shown to be advantageous. The importance of avoiding hypothermia in any treatment strategy is not to be understated.Whilst a great deal of progress has been made regarding optimal temperature management in recent years, further studies will be needed to determine which patients would benefit the most from control of pyrexia and by which means this should be implemented. This narrative review is part of a series on the pathophysiology and management of pyrexia.

The Effect of Paracetamol on Core Body Temperature in Acute Traumatic Brain Injury: A Randomised, Controlled Clinical Trial

Background

Strategies to prevent pyrexia in patients with acute neurological injury may reduce secondary neuronal damage. The aim of this study was to determine the safety and efficacy of the routine administration of 6 grams/day of intravenous paracetamol in reducing body temperature following severe traumatic brain injury, compared to placebo.

Methods

A multicentre, randomised, blind, placebo-controlled clinical trial in adult patients with traumatic brain injury (TBI). Patients were randomised to receive an intravenous infusion of either 1g of paracetamol or 0.9% sodium chloride (saline) every 4 hours for 72 hours. The primary outcome was the mean difference in core temperature during the study intervention period.

Results

Forty-one patients were included in this study: 21 were allocated to paracetamol and 20 to saline. The median (interquartile range) number of doses of study drug was 18 (17–18) in the paracetamol group and 18 (16–18) in the saline group (P = 0.85). From randomisation until 4 hours after the last dose of study treatment, there were 2798 temperature measurements (median 73 [67–76] per patient). The mean ± standard deviation temperature was 37.4±0.5°C in the paracetamol group and 37.7±0.4°C in the saline group (absolute difference -0.3°C; 95% confidence interval -0.6 to 0.0; P = 0.09). There were no significant differences in the use of physical cooling, or episodes of hypotension or hepatic abnormalities, between the two groups.

Conclusion

The routine administration of 6g/day of intravenous paracetamol did not significantly reduce core body temperature in patients with TBI.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12609000444280

European Stroke Organisation (ESO) Guidelines for the Management of Temperature in Patients with Acute Ischemic Stroke

Background

Hyperthermia is a frequent complication in patients with acute ischemic stroke. On the other hand, therapeutically induced hypothermia has shown promising potential in animal models of focal cerebral ischemia. This Guideline Document presents the European Stroke Organisation guidelines for the management of temperature in patients with acute ischemic stroke.

Methods

A multidisciplinary group identified related questions and developed its recommendations based on evidence from randomized controlled trials elaborating the Grading of Recommendations Assessment, Development, and Evaluation approach. This Guideline Document was reviewed within the European Stroke Organisation and externally and was approved by the European Stroke Organisation Guidelines Committee and the European Stroke Organisation Executive Committee.

Results

We found low-quality evidence, and therefore, we cannot make any recommendation for treating hyperthermia as a means to improve functional outcome and/or survival in patients with acute ischemic stroke and hyperthermia; moderate evidence to suggest against routine prevention of hyperthermia with antipyretics as a means to improve functional outcome and/or survival in patients with acute ischemic stroke and normothermia; very low-quality evidence to suggest against routine induction of hypothermia as a means to improve functional outcome and/or survival in patients with acute ischemic stroke.

Conclusions

The currently available data about the management of temperature in patients with acute ischemic stroke are limited, and the strengths of the recommendations are therefore weak. We call for new randomized controlled trials as well as recruitment of eligible patients to ongoing randomized controlled trials to allow for better-informed recommendations in the future.

Initial body temperature in ischemic stroke: nonpotentiation of tissue-type plasminogen activator benefit and inverse association with severity

BACKGROUND AND PURPOSE

Body temperature (BT) is an important physiological factor in acute ischemic stroke. However, the relationship of initial BT to stroke severity and degree of benefit from thrombolytic therapy has been delineated incompletely.

METHODS

We analyzed the public data set of the 2 National Institute of Neurological Disorders and Stroke Tissue-Type Plasminogen Activator (tPA) stroke trials, comparing patients with lower (<37.0°C) and higher (≥37.0°C) presenting BT.

RESULTS

Among 595 patients (297 placebo and 298 tPA treated) with documented initial BT, 77.1% had initial BT <37.0°C and 22.9% ≥37.0°C. Patients with higher initial BT had lower baseline stroke severity in both tPA-treated patients (the National Institute of Health Stroke Scale median, 11 versus 15; P=0.05) and placebo-treated patients (median, 13 versus 16; P<0.01). Patients with higher initial BT also had lower infarction volume on computed tomography at 3 months in both tPA-treated patients (median, 9.6 versus 16.7 cm(3); P=0.08) and placebo-treated patients (median, 13.1 versus 28.1 cm(3); P=0.02), but no clinical outcome differences. Analysis of lytic treatment effect found no heterogeneity in the degree of tPA benefit in both higher and lower BT groups (≥37.0°C: odds ratio for the modified Rankin Scale 0-1 outcome, 2.55; 95% confidence interval, 1.05-6.21 and <37.0°C: odds ratio, 2.30; 95% confidence interval, 1.38-3.84; heterogeneity P=0.83).

CONCLUSIONS

In patients with hyperacute stroke, higher presenting temperatures are associated with less severe neurological deficits and reduced final infarct volumes. Presenting temperature does not modify the benefit of tPA on 3-month favorable outcome.